On Tuesday 2 January 2024 at 19:28 UTC, a TLS handshake exhaustion targeted a online casino customer in the Middle East. The attack peaked at 471.9 million requests per second and lasted 49 minutes. Traffic originated from 51 autonomous systems in 64 countries, predominantly compromised cloud VMs.
| Vector | TLS handshake exhaustion |
| Peak | 471.9 million requests per second |
| Duration | 49 min |
| Time to mitigation | 0.055 s |
| Attack traffic reaching origin | 0.073% |
| Legitimate traffic challenged | 0.79% |
Timeline
The attack was preceded by a ransom note demanding payment in Monero. Request rates on the targeted routes exceeded their hourly baseline by a factor of 571 within 7 seconds. The risk score of participating clients crossed the challenge threshold automatically and proof-of-work difficulty rose with origin load.
What the customer saw
Checkout conversion was unchanged compared with the same hour of the previous week.
Recommendations
- Lower challenge thresholds on authentication endpoints during high-risk events.
- Enable log streaming to your SIEM for faster correlation.
- Review allow-listed partner ranges quarterly.
Clear and practical, thanks.
We moved from a scrubbing provider to always-on last year; time to mitigation went from minutes to basically nothing.
Do you publish the edge IP ranges in a machine-readable format?